1. The free edges of your fingernails and toenails are technically called the:

A. Lunula (The lunula is the white crescent moon shape at the base of the nail)
B. Matrix (The matrix is the area under the nail where new nail cells are produced)
C. Hyponychium (This is the skin under the free edge of the nail)
D. Free edge

Correct answer: D

Rationale: The free edges of your fingernails and toenails are the parts that extend beyond the fingertip or toe. These edges are commonly referred to simply as the "free edge" because they are not attached to the skin. The lunula is the white crescent moon shape at the base of the nail, the matrix is the area under the nail where new nail cells are produced, and the hyponychium is the skin under the free edge of the nail. Therefore, the correct answer is D.

2. Which molecule allows for the selective passage of materials into and out of the cell?

A. DNA
B. Protein
C. Carbohydrate
D. Phospholipid bilayer

Correct answer: D

Rationale: The correct answer is D, the phospholipid bilayer. The phospholipid bilayer is the main component of the cell membrane, which acts as a selective barrier allowing certain molecules to pass through while blocking others. Its structure consists of hydrophilic heads facing outward towards the aqueous environments inside and outside the cell, while the hydrophobic tails face inward creating a semi-permeable barrier. DNA (A) is the genetic material of the cell and is located within the nucleus, not involved in material passage. Proteins (B) and carbohydrates (C) are important components of the cell membrane and play various roles, but they do not directly control the selective passage of materials in and out of the cell.

3. The outermost layer of your skin, responsible for waterproofing and providing a barrier against pathogens, is the:

A. Stratum basale (Basal layer)
B. Stratum corneum
C. Stratum granulosum
D. Stratum spinosum

Correct answer: B

Rationale: The correct answer is B: Stratum corneum. The stratum corneum is the outermost layer of the epidermis, consisting of dead skin cells (corneocytes) that are continuously shed and replaced. This layer is responsible for waterproofing the skin and providing a barrier against pathogens, UV radiation, and other environmental factors. The stratum basale (A) is the deepest layer of the epidermis where new skin cells are produced. The stratum granulosum (C) is the layer of the epidermis where cells begin to flatten and keratinization begins. The stratum spinosum (D) is the layer above the stratum granulosum, where cells become interconnected by desmosomes. Therefore, the stratum corneum is specifically designed to fulfill the functions of waterproofing and protecting against pathogens.

4. Locate the heart within the human body cavities.

A. Dorsal cavity
B. Ventral cavity
C. Thoracic cavity
D. Abdominal cavity

Correct answer: C

Rationale: Rationale: The heart is located within the thoracic cavity, specifically in the mediastinum, which is the central compartment of the thoracic cavity. The thoracic cavity is part of the ventral cavity, which also includes the abdominal cavity. The dorsal cavity refers to the posterior side of the body and does not contain the heart. The heart is situated in the thoracic cavity between the lungs and above the diaphragm, making option C the correct choice.

5. What is the electron configuration of an atom?

A. The arrangement of electrons in an atom's orbitals.
B. The number of protons in an atom's nucleus.
C. The number of neutrons in an atom's nucleus.
D. The number of electrons in an atom's valence shell.

Correct answer: A

Rationale: The electron configuration of an atom refers to the arrangement of electrons in the atom's orbitals. This arrangement determines the atom's chemical properties and behavior. The number of protons in an atom's nucleus (option B) is known as the atomic number, while the number of neutrons in an atom's nucleus (option C) contributes to the atom's mass number. The number of electrons in an atom's valence shell (option D) is important for understanding the atom's reactivity and bonding behavior.

6. Which type of muscle is found in the walls of hollow organs, such as the stomach and intestines, and is responsible for involuntary contractions to propel substances through the organs?

A. Cardiac muscle
B. Smooth muscle
C. Skeletal muscle
D. Striated muscle

Correct answer: b

Rationale: The correct answer is B: Smooth muscle. Smooth muscle is found in the walls of hollow organs like the stomach and intestines. It is responsible for involuntary contractions to move substances through these organs. Unlike skeletal muscle (answer C) and cardiac muscle (answer A), smooth muscle is not under voluntary control. Striated muscle (answer D) is a term that refers to both skeletal and cardiac muscle due to their striped appearance under a microscope, but smooth muscle does not have this striped appearance.